1. Field of the Invention
This invention relates to actuators having a shape memory alloy as a driving source, and more particularly to a shape memory alloy actuator for rotating a pair of rotary members simultaneously and symmetrically in such a manner that a butterfly moves its right and left wings, as well as to a butterfly device having such an actuator.
2. Prior Art
In the prior art any attempt to construct an actuator which performs the aforesaid function brought forth such disadvantages as the actuator being complicated in construction to a considerable extent, large in size, heavy in weight and high in manufacturing cost.